The hydroformylation of olefins into aldehydes (oxo synthesis) was discovered by Roelen in 1938 and has thus long been known for the synthesis of fatty alcohols. Aldehydes made by hydroformylating long-chain olefins are readily hydrogenated into primary alcohols. See "Higher Oxo Alcohols", Lewis F. Hatch, Wiley, New York, 1957; and "New Syntheses with Carbon Monoxide", Ed. J. Falbe, Springer-Verlag, New York, 1980. Hydroformylation (including suitable catalysts) and the conventional conversion of the resulting alcohols into anionic surfactants such as alkyl sulphates and alkyl alkoxysulphates are also described in "Anionic Surfactants--Organic Chemistry", Volume 56 of the Surfactant Science Series, Marcel Dekker, New York, 1996, all the foregoing references hereby being incorporated in their entirety. Nonionic surfactants, such as the products of ethoxylating the alcohols, are also available using conventional ethoxylation. See "Nonionic Surfactants", Volume 1 of the Surfactant Science Series, Marcel Dekker, New York, 1966 and "Surface Active Ethylene Oxide Adducts", N. Schonfeldt, Pergamon Press, New York, 1969, these volumes and the enclosed references where pertinent being incorporated in their entirety.
Sasol manufactures olefins using Fischer-Tropsch technology which has been shown to be suitable for the manufacture of detergent alcohols, and thereby, a wide range of surfactants. The F-T process was developed since the late 1940's, and has been successfully implemented by Sasol under the trade name "Synthol" in the early 1960's. The Synthol technology is based on circulating fluidized bed (CFB) reactors.
The fixed bed F-T reactors are in operation since the successful startup of the plant in 1956. In 1957 the first mention is made of the use of Sasol feedstocks in LAB production. See "Sasol, 1950-1975", by Johannes Meintjies, Tafelberg, Cape Town, 1975, p 90; 92 (ISBN 0-624-00780-4).
Since the start of the F-T commercial units, research on both the process as well as the products has been undertaken. This led to the commercialisation of two new reactor types for the F-T reaction being the Sasol Advanced Synthol reactor (SAS) and the Slurry Bed F-T Reactor. This resulted in even better process efficiency at lower capital and operating cost.
All the F-T reactors produce a variety of valuable chemicals. One of the major product groups is olefins. Olefins produced include linear alpha olefins, mono-methyl branched alpha olefins, di- and tri-methyl branched alpha olefins and significantly lesser amounts of other branched and/or linear internal olefins. When the products of these reactors are worked up by distillation and/or other separations techniques and hydroformylated or oxydized by any similar technique, new detergent alcohol mixtures are obtained. The preferred method is separation via distillation and hydroformylation.
The same olefins can be produced using shorter chains of olefins C.sub.3 to C.sub.8 by adding, as a process step, dimerisation or oligomerization. Typically dimerisation of single carbon number fractions or mixtures thereof. Preferably a mixture of C.sub.7 to C.sub.9 or the single cuts C.sub.7 or C.sub.8 or C.sub.9. Oligomerization will typically be single carbon cuts or mixtures from C.sub.3, C.sub.4, C.sub.5, C.sub.6 that is oligomerized to C.sub.9 to C.sub.24.
These novel mixtures are technically advantageous when converted to various surfactants (some of the effects are described in an article called: "Fatty OXO-Alcohols: Relation between the alkyl chain structure and the performance of the derived AE, AS, AES" by A. Zatta et. al., World Surfactants Congress, 4.sup.th (1996), Volume 1, 213-226, CESIO), and economically attractive for the manufacturer of detergents. Also refer to WO 9701521 A1 published Jan. 16, 1997 assigned to Sastech, which is based on 95ZA-0005405 of Jun. 29, 1995. These documents are by means of reference incorporated herein in their entirety.
The detergent and cleaning products industries being old and well established, there are numerous publications on the use and incorporation of surface active agents (surfactants) in detergents. Among the many which can be cited are those referenced in Mc Cutcheon's well-known formulary and in Kirk Othmer's Encyclopedia of Chemical Technology, 1st-4th editions, volumes in the hereinbefore-referenced Surfactant Science Series, and large numbers of patents. Collections useful to the formulator further include "Detergent Manufacture Including Zeolite Builders and Other New Materials", Ed. Sittig, Noyes Data Corp., New Jersey, 1979, "Detergents and Textile Washing", G. Jakobi, A. Lohr et al, VCH Publishers, New York, 1987, and "Liquid Detergents", Volume 67 in the Surfactant Science Series, Ed. K-Y. Lai, Marcel Dekker, New York, 1997.
In the recent past, there has been an increasing desire from the manufacturer(s) of detergents to provide more soluble and cool-water effective cleaning compositions. This stems from the fact that in many countries, washing temperatures are on the decline. It is highly desirable to be able to clean fabrics and other articles in cool or cold water because of the energy economy, due to the large number of consumers who do not have access to convenient sources of hot water, and because cool water washing is less damaging and shrinking to fabrics. The greater use of more delicate synthetic fibers also contributed to the cooler washes. As has now been discovered, there is a very good "fit" between the need of the detergent manufacturer and what is now available from Sasol in the form of certain mixtures of methyl branched and some linear detergent alcohols as precursors for surfactant manufacture (especially methyl branched primary alcohols). Specifically, it is predicted from theory and observed behavior that methyl branching will enhance solubility of a surfactant without negatively affecting surfactant performance. A general rule for ionic surfactants is that the critical micelle concentration (cmc) is halved by the addition of one methylene group to a straight chain hydrophobic tail attached to a single hydrophilic group. See the hereinbefore-referenced Vol. 56 in the Surfactant Science Series.
One other desire from a manufacturing point of view is that detergents need to be less toxic and less irritating to the skin. These new detergent alcohols have the further advantages from a toxicity point of view as stated in "Environmental and Human safety of Major surfactants" by S. S. Talmage, pp 59,Chapter 4. This publication is hereby being incorporated in its entirety.
Specific work on the benefits of mono branched alcohols (this work includes methyl branching) versus linear alcohols is already demonstrated in the work of A. Zatta et al previously mentioned.
Accordingly it is an object herein to provide novel detergent surfactants derived from alcohol mixtures from hydroformylated F-T olefins such as those derived from all Sasol's F-T Reactors, and all manner of cleaning and detergent products making use of the advantageous properties of these materials.